[FIX]Fixed code for merge related problem(instanciate a QWeb2.Engine for each session).
[FIX]Fixed code for merge related problem(instanciate a QWeb2.Engine for each session).

akretion/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web